1. Field of the Invention
The present invention relates to an image processing apparatus and an image processing method whereby code images can be handled, and a program therefor, and relates more particularly to an image processing apparatus and an image processing method for controlling display of coded information, and a program therefor.
2. Description of the Related Art
When an original document is prepared by the printing of electronic data, it is difficult to perform the management of security for the original, and thus, the level of the security provided for the original is presently low.
Therefore, techniques for providing security measures for the original have been proposed that seek to identify a route, or routes, by which information may be leaked. As one of these proposed techniques for identifying an information leakage route, or routes, a code image (using two-dimensional code or a graphical image, such as an electronic watermark) is added to a medium, such as paper, and recording user information on the original.
User information in this case includes not only a user name, but also other information that identifies the creator of the original, such as a printing date and time and the serial number of a multifunction peripheral (MFP).
In Japanese Patent Laid-Open No. 2008-131522, a technique is disclosed whereby user information can be included in a two-dimensional code image of a provided size that can include a predetermined volume of information. In this case, two types of user information can be included.
Also for digital MFPs, there have recently been more cases involving the unauthorized release of the original, and a security measure technique is provided whereby an MFP performs printing while embedding user information in the above described two-dimensional code.
An example two-dimensional code to be embedded in a document is a QR Code (a registered trademark) disclosed in Japanese Patent Laid-Open No. H04-009963(1992). The QR Code is a two-dimensional code for general-purpose use. Therefore, the QR Code may be employed as a two-dimensional code, and be added to an original along with user information that is embedded in the QR Code. The MFP includes a function for displaying and outputting contents obtained by reading the two-dimensional code.
Further, in order to express the data list, the number of data sets and the data type for user information, a data identifier, a data format version and a data format revision may be jointly embedded in the two-dimensional code. Then, when the MFP reads the two-dimensional code, the MFP examines the data identifier, the data format version and the data format revision to determine whether the two-dimensional code is one that can be processed by the MFP, and provides control by either displaying or not displaying user information, or by selecting items to be displayed.
Here, the data format version and the data format revision included in the two-dimensional code will be described.
In the specification of the present invention, the terms “data format version” and “data format revision” are defined as information to be employed to manage or identify the list of data included as embedded information that is obtained by reading the two-dimensional code.
For performing a data conversion for the two-dimensional code (conversion into data consisting of a sequence of 0s and 1s), the version number (Version), which is information indicating the module size of two-dimensional code, an error correction level, binary data and information relative to a mode indicating a character code are generally employed. The “data format version” and the “data format revision” are provided separately from the information that is described above, and are employed to interpret information that has been embedded in two-dimensional code.
For a newly developed MFP that can support next-generation two-dimensional codes, for which the type and the volume of information to be embedded are changed, assume, for example, that a new function is added to the two-dimensional code function employed for a conventional MFP.
In this case, the data format version or/and the data format revision of the next-generation two-dimensional code are updated by incrementing the numerical value.
A difference between the data format version and the data format revision is that when the numerical value of the data format version is incremented, there is no guarantee that a currently employed MFP can interpret embedded information (recognition of embedded information), and then, only when the numerical value of the data format revision has been incremented, interpretation of embedded information can be performed by an MFP currently employed.
For example, in a case wherein a list of data for user information is changed, or wherein a new item for user information is defined, the numerical value of the data format version is incremented.
In a case wherein a change performed for the data format guarantees that interpretation can be performed for the items of user information already supported by the existing MFP, the numerical value of the data format revision is incremented. For example, in a case wherein a new user information item is added to the end of the user information conventionally designated, the information items located before the added item can be interpreted by the existing MFP. Therefore, such a change corresponds to incrementing of the numerical value of the data format revision.
A usage method assumed for the data format version and the data format revision will now be described. Data for the data format version and the data format revision are allocated at the same positions in the embedded information, regardless of the version or the revision. With this structure, even when the version or the revision differs, or the format for embedded information differs, the MFP can employ the embedded information to interpret the version information and the revision information.
The data format version is incremented when the format of the embedded information, consisting of two-dimensional code, is incompatible, and must therefore be changed. Thus, the data format version is changed in order to greatly alter the functional specifications provided by the two-dimensional code, so that the functional specifications differ from those for the existing MFP. For example, assume that the data list for user information included in the embedded information, which is defined in the data format version that precedes the latest change, represents a user name (32 bytes), a printing date and time (12 bytes) and a job type (4 bytes), in the named order. Further, assume that the data list for user information in the data format version of the next generation, which is incompatible, represents password information (20 bytes), a management ID (16 bytes), an email address (32 bytes) and a registration number (8 bytes), in the named order. In this case, since the list of data and the number of items are changed due to the change in the data format version, the existing MFP can decode the two-dimensional code, but can neither interpret nor identify the obtained data.
As for the data format revision, the numerical value is incremented in a case wherein format changing is performed to maintain the format compatibility of the embedded information of the two-dimensional code. This change is performed in order to extend or to change the specifications for the two-dimensional code while maintaining compatibility. For example, assume that the data list of user information, which is included in the embedded information defined in the data format revision that precedes the latest change, represents a user name (32 bytes), a printing date and time (12 bytes) and a job type (4 bytes), in the named order. Further, assume that for the compatible data format revision for the next generation, the name of a department is additionally provided at the last data position of the user information in the data format that precedes the latest change. In this case, the MFP currently being employed can interpret only the embedded information for the data format revision that precedes the latest one. Therefore, of the user information allocated by the latest data format revision, the existing MFP can interpret only the three items of user information allocated by the data format revision preceding the latest change. Thus, these information items can be handled in accordance with the specifications provided for the existing MFP.